Compositions having HASE rheology modifiers

ABSTRACT

A monomer compound that contains at least one polymerizable functional group per molecule, and at least one bicycloheptyl-, bicycloheptenyl-, or branched (C 5 -C 42 )alkyl-polyether radical per molecule, wherein the bicycloheptyl- or bicycloheptenyl-polyether radical may optionally be substituted on one or more of the ring carbon atoms by one or two (C 1 -C 6 )alkyl groups per ring carbon atom is useful in making polymers, particularly pH responsive polymers.

This application is a divisional application of U.S. patent applicationSer. No. 12/803,386, filed Jun. 25, 2010, now U.S. Pat. No. 8,071,674,which is a continuation of U.S. patent application Ser. No. 11/443,919,filed May 31, 2006, now U.S. Pat. No. 7,772,421, each of which claimsthe benefit of U.S. Provisional Patent Application Ser. No. 60/686,083,filed May 31, 2005.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to HASE rheological additives for aqueoussystems and emulsions. More particularly, the present invention relatesto a pH-responsive composition and a method useful for modifying therheological properties of aqueous emulsions.

2. Description of Related Art

Rheological additives are chemical compositions, which, added even insmall amounts, modify a liquid system's rheological properties, such asviscosity and response to shear. Such additives or thickeners may beused in a variety of liquid systems including aqueous systems such aspaints, aqueous inks, and personal care products. The additives improvethe rheological properties by also affecting the dispersion, suspensionand emulsification of pigments, binders and other solids within avehicle.

Conventional rheological additives include those of natural andsynthetic origin. Useful natural thickeners include, for example, guargum, pectin, xanthan gum, and alginate. Useful synthetic thickenersinclude, for example, hydrophobically modified ethoxylated urethanes(HEUR), ethylcellulose methylcellulose, hydroxyethylcellulose (HEC),hydroxymethylcellulose, carboxymethylcellulose, and other modifiedcellulosics.

Conventional natural and synthetic polymers have limitations withrespect to use as thickeners in aqueous systems, particularly in paintsand coatings. In general, they do not provide a rheological profilesuitable for adequate viscosity control, splatter resistance and flowproperties required in paints and coatings. For example, HEC swellsrapidly in water and forms lumps, which are not readily dispersible.

Hydrophobically modified alkali soluble emulsion (HASE) polymer systemsare commonly employed to modify the rheological properties of aqueousemulsion systems. Under the influence of a base, organic or inorganic,the HASE particles gradually swell and expand to form athree-dimensional network by intermolecular hydrophobic aggregationbetween HASE polymer chains and/or with components of the emulsion. Thisnetwork, combined with the hydrodynamic exclusion volume created by theexpanded HASE chains, produces the desired thickening effect. Thisnetwork being sensitive to applied stress, breaks down under shear andrecovers when the stress is relieved. Such rheological properties areparticularly desirable for paints and coatings because they make theformulation easy to apply onto a surface while providing the thicknessneeded for uniform coverage and avoid spattering.

HASE polymer systems can be prepared from the following monomers: (a) anethylenically unsaturated carboxylic acid, (b) a nonionic ethylenicallyunsaturated monomer, and (c) an ethylenically unsaturated hydrophobicmonomer. Representative HASE polymer systems include those shown in EP226097 B1, EP 705852 B1, U.S. Pat. No. 4,384,096, and U.S. Pat. No.5,874,495.

Therefore, polymeric thickeners are desired in the industry as analternative for HEC and similar cellulosics. Such paints should benon-biodegradable, free of toxic by-products, economical to manufacture,and exhibit excellent storage stability.

It would be desirable to have a HASE system wherein rheologicalproperties are improved. In particular, it would be desirable to have aHASE system that provides enhanced rheological properties in paints andcoatings. Further in particular, it would be desirable to have a HASEsystem that provides improved viscosity control, splatter resistance andflow properties in paints and coatings.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a plot diagram of the viscosity profiles of HASE polymer/paintlatex mixtures of the present invention.

FIG. 2 shows the viscosity at 0.1 s⁻¹ shear rate as a function of addedsurfactant for HASE polymer/paint latex mixtures of the presentinvention.

FIG. 3 shows the viscosity at 100 s⁻¹ shear rate as a function of addedsurfactant for HASE polymer/paint latex mixtures of the presentinvention.

FIG. 4 shows the viscosity at 7197 s⁻¹ shear rate as a function of addedsurfactant for HASE polymer/paint latex mixtures of the presentinvention.

SUMMARY OF THE INVENTION

In a first aspect, the present invention is directed to a monomercompound comprising:

at least one polymerizable functional group per molecule, and

at least one bicycloheptyl-, bicycloheptenyl-, or branched(C₅-C₄₂)alkyl-polyether radical per molecule, wherein the bicycloheptyl-or bicycloheptenyl-polyether radical may optionally be substituted onone or more of the ring carbon atoms by one or two (C₁-C₆)alkyl groupsper carbon atom.

In a second aspect, the present invention is directed to a polymercomprising one or more monomeric units, each comprising at least onebicycloheptyl-, bicycloheptenyl- or branched (C₅-C₄₂)alkyl-polyetherradical per molecule, wherein the bicycloheptyl- orbicycloheptenyl-polyether radical may optionally be substituted on oneor more of the ring carbon atoms by one or two (C₁-C₆)alkyl groups perring carbon atom.

In a third aspect, the present invention is directed to a pH responsivepolymer, comprising, based on the total weight of monomers,

-   (a) from about 25 to about 70 percent by weight acid monomeric    units, each independently comprising a carboxylic acid-functional    substituent group,-   (b) from about 30 to about 70 percent by weight nonionic monomeric    units, each independently comprising a nonionic substituent group,    and-   (c) from about 0.05 to about 20 percent by weight hydrophobic    monomeric units, each independently comprising at least one    bicycloheptyl-, bicycloheptenyl-, or branched    (C₅-C₄₂)alkyl-polyether radical per monomeric unit, wherein the    bicycloheptyl- or bicycloheptenyl-polyether radical may optionally    be substituted on one or more of the ring carbon atoms by one or two    (C₁-C₆)alkyl groups per carbon atom.

In a fourth aspect, the present invention is directed to a pH-responsivecomposition having A) a solvent and B) a polymer dispersed therein. Thepolymer has the following:

-   (a) about 25 to about 70 weight percent based on total monomers of    at least one C₃-C₈ alpha beta-ethylenically unsaturated carboxylic    acid monomer of the structure (II):    RCH═C(R′)COOH  (II)    -   wherein R is H, CH₃, or —CH₂COOX; and wherein if R is H, then R′        is H, C₁-C₄ alkyl, or —CH₂COOX; if R is —C(O)OX, then R′ is H or        —CH₂C(O)OX; or if R is CH₃, then R′ is H; and X, if present, is        H or C₁-C₄ alkyl;-   (b) about 30 to about 70 weight percent based on total monomers of    at least one copolymerizable non-ionic C₂-C₁₂ alpha    beta-ethylenically unsaturated monomer of the structure (III):    H₂C═CYZ  (III)    -   wherein Y is H, CH₃, or Cl; Z is CN, Cl, —COOR′, —C₆H₄R′,        —COOR″, or —HC═CH₂; and wherein R is C₁-C₈ alkyl or C₂-C₈        hydroxy alkyl; and wherein R′ is H, Cl, Br, or C₁-C₄ alkyl; and        R″ is C₁-C₈ alkyl; and-   (c) about 0.05 to about 20 weight percent based on total monomer    weight of at least one ethylenically unsaturated monomer represented    by the structure selected from a group consisting of structure IV    and structure VI; wherein structure IV represents an ester of an    alkoxylated fatty alcohol

-   -   wherein R is H or CH₃; wherein R₁ is a —(CH₂)_(p)H alkyl chain;        wherein p is an integer from 1 to about 4; wherein j is an        integer from 1 to about 50; wherein k is an integer from 0 to        about 20; wherein h is 1 or 2; and wherein X has the following        structure (V):

-   -   wherein m and n are, independently, are positive integers from 1        to 39 and m+n represents an integer from 4 to 40; and wherein        structure VI is an ester of an alkoxylated nopol

-   -   wherein R₃ is H or CH₃; R₄ is an alkyl chain containing 1 to        about 4 carbons; M is an integer from 1 to about 50; and N is 0        or an integer of less than or equal to M.

The pH responsive polymer is useful for modifying the rheologicalproperties of an aqueous composition, and can be added to an aqueouspaint or coating composition to provide desirable properties, such asimproved viscosity and flow control as well as improved spatterresistance.

The pH responsive polymer of the present invention is useful in, forexample, personal care applications, such as shampoos, body wash, handsoap, lotions, creams, conditioners, shaving products, facial washes,neutralizing shampoos, personal wipes, and skin treatments, and in homecare applications, such as liquid detergents, laundry detergents, hardsurface cleansers, dish wash liquids, toilet bowl cleaners, as well asother applications, such as oil field and agrochemical applications.

In one embodiment, the present invention is directed to an aqueouscomposition, comprising water and the above described pH responsivepolymer. In one embodiment, the aqueous composition exhibitsviscoelastic properties.

It is a still yet further object of the invention to have compounds,i.e., monomers, corresponding to structures III and V. There may also bepolymers and copolymers thereof that differ from the HASE polymersdescribed above.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the terminology “(C_(r)-C_(s))” in reference to anorganic group, wherein r and s are each integers, indicates that thegroup may contain from r carbon atoms to s carbon atoms per group.

As used herein, the term “alkyl” means a monovalent straight or branchedsaturated hydrocarbon radical, more typically, a monovalent straight orbranched saturated (C₁-C₂₂)hydrocarbon radical, such as, for example,methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl,n-hexyl, n-octyl, and n-hexadecyl.

As used herein, the term “cycloalkyl” means a saturated(C₅-C₂₂)hydrocarbon radical that includes one or more cyclic alkylrings, such as, for example, cyclopentyl, cycloheptyl, cyclooctyl, and“bicyloalkyl” means a cycloalkyl ring system that comprises twocondensed rings, such as bicycloheptyl.

As used herein, the term “alkenyl” means an unsaturated straight orbranched hydrocarbon radical, more typically an unsaturated straight,branched, (C₂-C₂₂) hydrocarbon radical, that contains one or morecarbon-carbon double bonds, such as, for example, ethenyl, n-propenyl,iso-propenyl,

As used herein, the term “cycloalkenyl” means an unsaturated (C₅-C₂₂)hydrocarbon radical, that contains one or more cyclic alkenyl rings,such as cyclohexenyl, cycloheptenyl, and “bicycloalkenyl” means acycloalkenyl ring system that comprises two condensed rings, such asbicycloheptenyl.

The “bicyclo[d.e.f]” notation is used herein in reference tobicycloheptyl and bicycloheptenyl ring systems in accordance with thevon Baeyer system for naming polycyclic compounds, wherein a bicyclicsystem is named by the prefix “bicyclo-” to indicate number of rings inthe system, followed by a series of three arabic numbers, listed indescending numerical order, separated by full stops, and enclosed insquare brackets, to indicate the respective number of skeletal atoms ineach acyclic chain connecting the two common atoms (the “bridgeheadatoms”), excluding the bridgehead atoms.

Suitable polymerizable functional groups include, for example, acrylo,methacrylo, acrylamido, methacrylamido, diallylamino, allyl ether, vinylether, α-alkenyl, maleimido, styrenyl, and α-alkyl styrenyl groups.

In one embodiment, the bicycloheptyl- or bicycloheptenyl- or branched(C₅-C₄₂)alkyl-polyether radical is according structure (I):—R¹³—R¹²—R¹¹  (I)

wherein:

-   -   R¹¹ is bicycloheptyl, bicycloheptenyl, or branched        (C₅-C₄₂)alkyl, wherein the bicycloheptyl or bicycloheptenyl        group may optionally be substituted on one or more of the ring        carbon atoms by one or two (C₁-C₆)alkyl groups per ring carbon        atom,    -   R¹² is absent, or is a bivalent linking group, and    -   R¹³ is a bivalent polyether group.

In one embodiment, R¹¹ is a branched alkyl group according to structure(VII):

wherein:

-   -   R¹⁹ and R²⁰ are each independently (C₁-C₄₀)alkyl, and    -   b is an integer of from 0 to 39, provided that R¹¹, that is,        R¹⁹, R²⁰ and the —(CH₂)_(b)— radical taken together, comprises a        total of from about 6 to about 42, more typically about 12 to        about 42, carbon atoms.

In one embodiment, R¹¹ is bicyclo[d.e.f]heptyl orbicyclo[d.e.f]heptenyl, wherein d is 2, 3, or 4, e is 1 or 2, f is 0 or1, and the sum of d+e+f=5, and which may, optionally, be substituted onone or more of the ring carbon atoms by one or more (C₁-C₆)alkyl groups.More typically, R¹¹ is:

-   (i) a bicyclo[3.1.1]heptyl or bicyclo[3.1.1]heptenyl group that is    bonded to R¹², if present, or to R¹³, if R¹² is not present, via its    carbon atom at the 2-position and is typically substituted on its    carbon atom at the 6-position by one or two (C₁-C₆)alkyl radicals,    more typically by two methyl radicals, or-   (ii) a bicyclo[3.1.1]heptyl or bicyclo[2.2.1]heptenyl group that is    bonded to R¹², if present, or to R¹³, if R¹² is not present, via its    carbon atom at the 2-position or 3-position and is typically    substituted on its carbon atom at the 7 position by one or two    (C₁-C₆)alkyl radicals, more typically by two methyl radicals,

In one embodiment, R¹² is a bivalent oxyalkylene or oxyalkylene oxyradical which may optionally be substituted on one or more carbon atomsof the radical with alkenyl, cycloalkyl, or cycloalkenyl. In oneembodiment, R¹² is —OC_(v)H_(2v)—, wherein v is an integer of from 1 to10, more typically from 1 to 6, even more typically from 2 to 4. In oneembodiment, R¹² is

or —O—CH(R¹⁶)—CH(R¹⁷)—O—, wherein R¹⁴, R¹⁵, R¹⁶, and R¹⁷ are eachindependently H, alkyl, alkenyl, cycloalkyl or cycloalkenyl, moretypically H, (C₁-C₆)alkyl, or (C₁-C₆)alkenyl, and even more typically H,methyl, or ethyl.

In one embodiment, R¹³ is a bivalent polyoxyalkylene group according tostructure (VIII):

wherein:

-   -   p′ and q are independently integers of from 2 to 5, more        typically 2 or 3,    -   each r is independently an integer of from 0 to about 80, more        typically from 0 to about 50,    -   each s is independently an integer of from 1 to about 80, more        typically from about 1 to about 50, and    -   t is an integer of from 1 to 50, provided that the product of t        multiplied times the sum of r+s is less than or equal to about        100.

In embodiments wherein —(OC_(p′)H_(2p′))— and (—(OC_(q)H_(2q))—,oxyalkylene units with p′ not equal to q, are each present, therespective oxylakylene units may be arranged randomly, in blocks, or inalternating order.

In one embodiment, the monomer of the present invention is according tostructure (IX):R¹⁸—R¹³—R¹²—R¹¹  (IX)wherein:

R¹¹, R¹², and R¹³ are each defined as above, and

R¹⁸ is acrylo, methacrylo, acrylamido, methacrylamido, diallylamino,allyl ether, vinyl ether, α-alkenyl, maleimido, styrenyl, or α-alkylstyrenyl.

In one embodiment, R¹⁸ is acrylo or methacrylo.

In one embodiment, the monomer of the present invention is a compoundaccording to structure (X):

wherein R²¹ is H or methyl, and R¹⁹, R²⁰, b, p′, q, r, s, and t are eachas described above.

In one embodiment, the monomer of the present invention is a compoundaccording to structure (XI):

wherein R²¹ is H or methyl, and p′, q, r, s, and t are each as describedabove.

Suitable bicycloheptyl- and bicycloheptenyl-moieties may be derivedfrom, for example, terpenic compounds having core (non-substituted) 7carbon atom bicyclic ring systems according to structures (XII)-(XVII):

For example, a bicycloheptenyl intermediate compound (XVIII), known as“Nopol”:

is made by reacting β-pinene with formaldehyde, and a bicycloheptylintermediate compound (XIX), known as “Arbanol:

is made by isomerization of α-pinene to camphene and ethoxyhydroxylationof the camphene.

In one embodiment, a bicycloheptyl- or bicycloheptenyl-intermediate isalkoxylated by reacting the bicycloheptyl- or bicycloheptenylintermediate with one or more alkylene oxide compounds, such as ethyleneoxide or propylene oxide, to form a bicycloheptyl-, orbicycloheptenyl-polyether intermediate. The alkoxylation may beconducted according to well known methods, typically at a temperature inthe range of about 100° to about 250° C. and at a pressure in the rangeof from about 1 to about 4 bars, in the presence of a catalyst, such asa strong base, an aliphatic amine, or a Lewis acid, and an inert gas,such as nitrogen or argon.

The bicycloheptyl-, or bicycloheptenyl-polyether monomer is then formedby addition of a polymerizable functional group to the bicycloheptyl- orbicycloheptenyl-polyether intermediate, by, for example, esterification,under suitable reaction conditions, of the bicycloheptyl- orbicycloheptenyl-polyether intermediate with, for example, methacrylicanhydride.

Alternatively, a monomer comprising a polymerizable functional group,such as for example, polyethylene glycol monomethacrylate, can bealkoxylated to form a polyether monomer and the alkoxylated monomer thenreacted with the bicycloheptyl- or bicycloheptenyl-intermediate to formthe bicycloheptyl-, or bicycloheptenyl-polyether monomer.

In one embodiment, the polymer of the present invention comprises fromabout 30 to about 65, more typically from about 30 to about 60, percentby weight acid monomeric units, from about 35 to about 70, moretypically from about 40 to about 60, percent by weight nonionicmonomeric units, and from about 1 to about 15, more typically from about2 to about 10, percent by weight hydrophobic monomeric units.

The present invention provides a pH-responsive composition useful formodifying the rheological properties of an aqueous emulsion.

In one embodiment, the acid monomer units of the pH responsive polymerare derived from one or more ethylenically unsaturated carboxylic acidmonomer, such as, for example, methacrylic acid.

In one embodiment, the nonionic monomer units of the pH responsivepolymer are derived from one or more ethylenically unsaturated nonionicmonomer, such as an alkyl or hydroxyalkyl ester of an acid monomer, forexample, 2-ethylhexylacrylate.

In one embodiment, the hydrophobic monomeric units of the polymer of thepresent invention each comprise a pendant substituent group according tostructure (I), wherein R¹¹, R¹², and R¹³ are each as described above.

In one embodiment, the polymer of the present invention is prepared fromthe following components: (A) about 25 to 70 weight percent based ontotal monomers of a C₃-C₈ alpha beta-ethylenically unsaturatedcarboxylic acid monomer; (B) about 30 to 70 weight percent based ontotal monomers of at least one copolymerizable non-ionic C₂-C₁₂ alphabeta-ethylenically unsaturated monomer, and (C) about 0.05 to about 20weight percent based on total monomer weight of a selected hydrophobicethylenically unsaturated monomer.

The effectiveness of these liquid emulsion polymers as a pH-responsivethickener for many aqueous products is dependent on the characteristicsof each monomer. Component A provides the requisite pH-responsivenessand hydrophilicity. Component B provides an extended polymer backboneand allows adjustment of the hydrophilic/lipophilic balance. Component Cprovides an in situ, bound surfactant to control the rheology of theaqueous system containing the solubilized polymeric thickener. Theproportions of the individual monomers can be varied to achieve optimumproperties for specific applications.

Component A is at least one C₃-C₈ alpha beta-ethylenically unsaturatedcarboxylic acid monomer of the structure (II):RCH═C(R′)COOH  (II)wherein if R is H, then R′ is H, C₁-C₄ alkyl, or —CH₂COOX; if R is—C(O)OX, then R′ is H or —CH₂C(O)OX; or if R is CH₃, then R′ is H; andX, if present, is H or C₁-C₄ alkyl.

Carboxylic acids useful as an ethylenically unsaturated carboxylic acidmonomer and as component (A) include itaconic acid, fumaric acid,crotonic acid, acrylic acid, methacrylic acid, and maleic acid. Apreferred carboxylic acid monomer is methacrylic acid or a mixturethereof with one or more other carboxylic acids. Half esters are alsosuitable.

Component A is present at about 25 to 70, preferably about 30 to about65, and most preferably about 35 to about 60 weight percent based ontotal monomer weight of components A, B, and C.

Component B is at least one copolymerizable non-ionic C₂-C₁₂ alphabeta-ethylenically unsaturated monomer of the structure (III):H₂C═CYZ  (III)wherein Y is H, CH₃, or Cl; Z is CN, Cl, —COOR′, —C₆H₄R′, —COOR, or—HC═CH₂; R is C₁-C₈ alkyl or C₂-C₈ hydroxy alkyl; R′ is H, Cl, Br, orC₁-C₄ alkyl, and R″ is C₁-C₈ alkyl.

Monomers useful as the ethylenically unsaturated nonionic monomer and ascomponent B include, but are not limited to, C₁-C₈ alkyl and C₂-C₈hydroxyalkyl esters of acrylic and methacrylic acid. Useful monomersinclude ethyl acrylate, ethyl methacrylate, methyl methacrylate,2-ethylhexyl acrylate, butyl acrylate, butyl methacrylate,2-hydroxyethyl acrylate, 2-hydroxybutyl methacrylate, styrene,vinyltoluene, t-butylstyrene, isopropylstyrene, and p-chlorostyrene,vinyl acetate, vinyl butyrate, vinyl caprolate; acrylonitrile,methacrylonitrile, butadiene, isoprene, vinyl chloride, vinylidenechloride, and combinations thereof. A preferred monomer is ethylacrylate alone or in combination with styrene, hydroxyethyl acrylate,acrylonitrile, vinyl chloride or vinyl acetate.

Component B is present at about 30 to about 70, preferably about 35 toabout 70, and more preferably from about 40 to about 60 weight percentbased on total monomer weight of components A, B, and C. Preferably, thehydrophilic balance of the copolymer product can be adjusted by theappropriate selection of the unsaturated nonionic monomer.

Component C is at least one hydrophobic ethylenically unsaturatedmonomer selected from among those represented in structure (IV) orstructure (VI). Structure (IV) has the following structure:

wherein R is H or CH₃; wherein R₁ is a —(CH₂)_(p)H alkyl chain; whereinp is an integer from 1 to about 4; wherein j is an integer from 1 toabout 50 and preferably about 10 to about 40; wherein k is an integerfrom 0 to about 20, wherein h is 1 or 2 and wherein X has the followingstructure (V):

wherein m and n are independently positive integers, and m+n representan integer from 4 to 40 and preferably 4 to 20. In a preferredstructure, k is equal to 0, 1 equal to is 25, h is equal to 1, n isequal to 8, and m is equal to 10.

Branched esters corresponding to component B are preferably synthesizedfrom Guerbet alcohols. These alcohols have a branched structure andexhibit oxidative stability at elevated temperatures.

Structure (VI) has the following structure:

wherein R₃ is H or CH₃; R₄ is an alkyl chain containing 1 to about 4carbons; M is an integer from 1 to about 50 and preferably about 10 toabout 40; and N is an integer having a value of 0 or an integer lessthan or equal to M. In a most preferred structure, R₃ and R₄ are CH₃, Mis equal to 25 and N is equal to 5.

Component C is present at about 0.05 to about 20, preferably about 1 toabout 15, and most preferably about 2 to about 10 weight percent basedon total monomer weight of components A, B, and C.

In one embodiment, the polymer composition of the present invention hasa solids content of up to about 60 wt % and, more typically about 20 toabout 50 wt %, based on the combined weight of the polymer of thepresent invention (including components A, B, and C) andemulsifiers/surfactants employed.

In one embodiment, the polymer composition of the present invention isin the form of an aqueous colloidal polymer dispersion. When the polymercomposition is in the form of an aqueous colloidal polymer dispersion,the composition is maintained at a pH of about 5 or less to maintainstability. More typically, the aqueous colloidal polymer dispersioncomposition has a pH of about 2 to about 3. When thickening of thecomposition is desired, the pH of the composition can be increased to avalue above about 5 by addition of a base to solubilize the polymer.

The polymer and polymer composition of the present invention can beconveniently prepared from the above-described monomers by conventionalemulsion polymerization techniques at an acid pH of about 5.0 or lessusing free-radical producing initiators, usually in an amount from 0.01percent to 3 percent based on the weight of the monomers. Polymerizationat an acid pH of about 5.0 or less permits direct preparation of anaqueous colloidal dispersion having relatively high solids contentwithout the problem of excessive viscosity.

The free-radical producing initiators typically are peroxygen compounds.Useful peroxygen compounds include inorganic persulfate compounds suchas ammonium persulfate, potassium persulfate, sodium persulfate;peroxides such as hydrogen peroxide; organic hydroperoxides, forexample, cumene hydroperoxide, and t-butyl hydroperoxide; organicperoxides, for example, benzoyl peroxide, acetyl peroxide, lauroylperoxide, peracetic acid, and perbenzoic acid (sometimes activated by awater-soluble reducing agent such as ferrous compound or sodiumbisulfite); and other free-radical producing materials or techniquessuch as 2,2′-azobisisobutyronitrile and high energy radiation sources.

Optionally, a chain transfer agent can be used. Representative chaintransfer agents are carbon tetrachloride, bromoform;bromotrichloromethane; and long-chain alkyl mercaptans and thioesters,such as n-dodecyl mercaptan, t-dodecyl mercaptan, octyl mercaptan,tetradecyl mercaptan, hexadecyl mercaptan, butyl thioglycolate, isooctylthioglycolate, and dodecyl thioglycolate. The chain transfer agents canbe used in amounts up to about 10 parts per 100 parts of polymerizablemonomers.

The composition has one or more emulsifiers. Useful emulsifiers includeanionic surfactants, nonionic surfactants, amphoteric surfactants, andzwitterionic surfactants. Preferred surfactants are anionic surfactants.Examples of anionic emulsifiers are the alkali metal alkyl arylsulfonates, the alkali metal alkyl sulfates and the sulfonated alkylesters. Specific examples of these well-known emulsifiers are sodiumdodecylbenzenesulfonate, sodium disecondary-butylnaphthalene sulfonate,sodium lauryl sulfate, disodium dodecyldiphenyl ether disulfonate,disodium n-octadecylsulfosuccinamate and sodium dioctylsulfosuccinate.Useful nonionic emulsifiers include, for example, common structuresbased on polyethylene oxide or oligosaccharides hydrophilic heads.

Optionally, other ingredients well known in the emulsion polymerizationart may be included, such as chelating agents, buffering agents,inorganic salts and pH adjusting agents.

Usually the copolymerization is carried out at a temperature betweenabout 60° C. and 90° C., but higher or lower temperatures may be used.The polymerization can be carried out batchwise, stepwise orcontinuously with batch and/or continuous addition of the monomers in aconventional manner.

The monomers can be copolymerized in such proportions, and the resultingemulsion polymers can be physically blended, to give products with thedesired balance of properties for specific applications. For example, ifa more viscous product is desired, the acid and surfactant monomercontent can be increased. Greater flexibility and coalescence can beobtained with higher amounts of ethyl acrylate. Addition of styrene as asecond nonionic vinyl monomer will increase to a higher pH theadjustment required to dissolve the emulsion in an aqueous coatingcomposition. Minor quantities of a polyfunctional monomer, such asitaconic or fumaric acid or isoprene to introduce a higher carboxylicacid content or limited crosslinking, provide further control of thesolubility of the emulsion polymer after pH adjustment.

Thus, by varying the monomers and their proportions, emulsion polymershaving optimum properties for particular applications can be designed.Particularly effective liquid emulsion polymer thickeners are obtainedby copolymerization of about 40 to about 50 weight percent ofmethacrylic acid, about 35 to about 50 weight percent of ethyl acrylate,and about 0.05 to 20 weight percent of the ester according to structuresIII and IV.

The copolymer products according to the present invention prepared byemulsion polymerization at an acid pH are in the form of stable aqueouscolloidal dispersions containing the copolymer dispersed as discreteparticles having average particle diameters of about 500 to about 3000 Åand preferably about 1000 to about 1750 Å as measured by lightscattering. Dispersions containing polymer particles smaller than about500 Å are difficult to stabilize, while particles larger than about 3000Å reduce the ease of dispersion in the aqueous products to be thickened.

These emulsion copolymers according to the present invention willnormally have number average molecular weights of at least about 30,000daltons as determined by gel permeation chromatography. In oneembodiment, the pH responsive polymer of the present invention exhibiteda number average molecular weight of from about 30,000 to about5,000,000 daltons, more typically from about 100,000 to about 2,000,000daltons, even more typically from about 1,000,000 to about 1,000,000daltons. To provide most effective thickening with copolymers that arewater-soluble when neutralized, molecular weights within the range ofabout 200,000 to about 5,000,000 daltons are preferred. In terms of astandard Brookfield viscosity measured as a 1 percent aqueous solutionin ammonium salt form at pH 9 and 25° C., a polymer with a viscosity ofabout 100 to about 1,000,000 cps, and preferably about 100 to about300,000 cps, is particularly desirable for many applications. Theaqueous dispersions of the copolymers contain about 10-50 weight percentof polymer solids and are of relatively low viscosity. They can bereadily metered and blended with aqueous product systems.

The polymers and polymer compositions according to the present inventionare pH-responsive. At the lower pH levels at which the emulsionpolymerization takes place, i.e., pH levels of 5 or less, thecomposition is relatively thin or non-viscous. When the pH of thepolymer dispersion is neutralized or adjusted by addition of a base to apH of about 5.5 or more, preferably about 6.5 to about 11, thecomposition thickens substantially. The composition turns fromsemi-opaque or opaque to translucent or transparent as viscosityincreases. Viscosity increases as polymer dissolves partially orcompletely in the aqueous phase of the composition. Neutralization canoccur in situ when the emulsion polymer is blended with the base andadded to the aqueous phase. Or, if desired for a given application,neutralization can be carried out when blending with an aqueous product.Useful bases include, but are not limited to, ammonia, an amine, sodiumhydroxide, potassium carbonate or the like.

In addition to emulsion polymerization, polymers according to thepresent invention can also be made using known solution polymerizationtechniques. The monomers can be dissolved in an appropriate solvent suchas toluene, xylene, tetrahydrofuran, or mixtures thereof. Polymerizationcan be accomplished in the time and at the temperature necessary, e.g.,60° C. to 80° C. and about 2 to 24 hours. The product can be obtainedthrough normal techniques, including solvent stripping.

The polymers and polymer compositions according to the present inventionare useful as water-soluble thickeners for a wide variety ofapplications ranging from cosmetics to oilfield drilling fluids, but areparticularly useful for aqueous paints and coatings.Solution-polymerized polymers can be used in solvent systems oremulsified by known techniques for use in aqueous systems. Other usesinclude latexes and detergents. Useful cosmetic compositions willtypically have an aqueous carrier, a pigment and/or cosmetic active, aHASE emulsion polymer, and optional adjuvants. Useful detergents andcleansers will typically have aqueous carrier, a HASE emulsion polymer,and optional adjuvants. Oilfield drilling fluids will typically have anaqueous carrier, HASE emulsion polymer as a thickener/viscositymodifier, and optional adjuvants. The oilfield drilling fluids areinjected into the oilfield formation. Useful latex coatings willtypically have an aqueous carrier, a HASE emulsion polymer, and optionaladjuvants.

The HASE emulsion polymers according to the present invention asdescribed herein are particularly useful as thickeners for a widevariety of water-based compositions. Such compositions include brine,slurries, and colloidal dispersions of water-insoluble inorganic andorganic materials, such as natural rubber, synthetic or artificiallatexes. The emulsion polymers of the invention are especially useful inareas requiring thickening at neutral pHs, such as in cosmetics.

In one embodiment, the aqueous composition comprising the pH responsivepolymer of the present invention exhibits viscoelastic properties atneutral to alkaline pH values, typically at pH values greater than orequal to about 5, more typically greater than or equal to about 5.5,even more typically of from about 6 to about 9.

Synthetic latexes take the form of aqueous dispersions/suspensions ofparticles of latex polymers. Synthetic latexes include aqueous colloidaldispersions of water-insoluble polymers prepared by emulsionpolymerization of one or more ethylenically unsaturated monomers.Typical of such synthetic latexes are emulsion copolymers ofmonoethylenically unsaturated compounds, such as styrene, methylmethacrylate, acrylonitrile with a conjugated diolefin, such asbutadiene or isoprene; copolymers of styrene, acrylic and methacrylicesters, copolymers of vinyl halide, vinylidene halide, vinyl acetate andthe like. Many other ethylenically unsaturated monomers or combinationsthereof can be emulsion polymerized to form synthetic latexes. Suchlatexes are commonly employed in paints (latex paints) and coatings. Thecomposition of the present invention may be added to latexes tomodify/increase viscosity.

The polymeric thickeners of this invention are advantageous for use withthe water-based compositions according to the foregoing description andwith compositions containing those materials, especially coatingcompositions of various types. Mixtures or combinations of two or morethickeners may be used, if desired. Of course the latex polymers used incoating compositions are preferably film-forming at temperatures about25° C. or less, either inherently or through the use of plasticizers.Such coating compositions include water-based consumer and industrialpaints; sizing, adhesives and other coatings for paper, paperboard,textiles; and the like.

Latex paints and coatings may contain various adjuvants, such aspigments, fillers and extenders. Useful pigments include, but are notlimited to, titanium dioxide, mica, and iron oxides. Useful fillers andextenders include, but are not limited to, barium sulfate, calciumcarbonate, clays, talc, and silica. The compositions of the presentinvention described herein are compatible with most latex paint systemsand provide highly effective and efficient thickening.

The polymer compositions of the present invention may be added toaqueous product systems at a wide range of amounts depending on thedesired system properties and end use applications. In latex paints, thecomposition is added such that the emulsion (HASE) polymer according tothe present invention is present at about 0.05 to about 5.0 weightpercent and preferably about 0.1 to about 3.0 weight percent based ontotal weight of the latex paint, including all of its components, suchas water, HASE polymer, latex polymer, pigment, and any adjuvants.

In formulating latexes and latex paints/coatings, physical propertiesthat may be considered include, but are not limited to, viscosity versusshear rate, ease of application to surface, spreadability, and shearthinning.

The pH responsive polymer of the present invention is suitable in thepreparation of personal care (cosmetics, toiletries, health and beautyaids, cosmeceuticals) and topical health care products, includingwithout limitation, hair care products, such as shampoos (includingcombination shampoos, such as “two-in-one” conditioning shampoos);post-shampoo rinses; setting and style maintenance agents includingsetting aids, such as gels and sprays, grooming aids, such as pomades,conditioners, perms, relaxers, hair smoothing products, and the like;skin care products (facial, body, hands, scalp and feet), such ascreams, lotions, conditioners, and cleansing products; anti-acneproducts; anti-aging products (exfoliant, keratolytic, anticellulite,antiwrinkle, and the like); skin protectants such as sunscreens,sunblock, barrier creams, oils, silicones, and the like; skin colorproducts (whiteners, lighteners, sunless tanning accelerators, and thelike); hair colorants (hair dyes, hair color rinses, highlighters,bleaches and the like); pigmented skin colorants (face and body makeups,foundation creams, mascara, rouge, lip products, and the like); bath andshower products (body cleansers, body wash, shower gel, liquid soap,soap bars, syndet bars, conditioning liquid bath oil, bubble bath, bathpowders, and the like); nail care products (polishes, polish removers,strengtheners, lengtheners, hardeners, cuticle removers, softeners, andthe like); and any aqueous acidic to basic composition to which aneffective amount of the associative polymer can be incorporated forachieving a beneficial or desirable, physical or chemical, effecttherein during storage and/or usage.

In one embodiment, the present invention is directed to a personal carecomposition comprising water, one or more surfactants, and a pHresponsive polymer according to the present invention.

In one embodiment, the personal care composition comprises, based on 100parts by weight (“pbw”) of the personal care composition, from about 10to about 80 pbw, more typically from about 20 to about 70 pbw, water,from about 1 to about 50 pbw of one or more surfactants and from about0.05 to about 20 pbw of the pH responsive polymer of the presentinvention.

Suitable surfactants include anionic surfactants, cationic surfactants,non-ionic surfactants, zwitterionic surfactants, and mixtures thereof.

Suitable anionic surfactants are known compounds and include, forexample, linear alkylbenzene sulfonates, alpha olefin sulfonates,paraffin sulfonates, alkyl ester sulfonates, alkyl sulfates, alkylalkoxy sulfates, alkyl sulfonates, alkyl alkoxy carboxylates, alkylalkoxylated sulfates, monoalkyl phosphates, dialkyl phosphates,sarcosinates, isethionates, and taurates, as well as mixtures thereof,such as for example, ammonium lauryl sulfate, ammonium laureth sulfate,triethanolamine laureth sulfate, monoethanolamine lauryl sulfate,monoethanolamine laureth sulfate, diethanolamine lauryl sulfate,diethanolamine laureth sulfate, lauric monoglyceride sodium sulfate,sodium lauryl sulfate, sodium laureth sulfate, potassium lauryl sulfate,potassium laureth sulfate, sodium trideceth sulfate, sodium tridecylsulfate, ammonium trideceth sulfate, ammonium tridecyl sulfate, sodiumcocoyl isethionate, disodium laureth sulfosuccinate, sodium methyloleoyl taurate, sodium laureth carboxylate, sodium tridecethcarboxylate, sodium monoalkyl phosphate, sodium dialkyl phosphate,sodium lauryl sarcosinate, lauroyl sarcosine, cocoyl sarcosinate,ammonium cocyl sulfate, sodium cocyl sulfate, potassium cocyl sulfate,monoethanolamine cocyl sulfate, sodium tridecyl benzene sulfonate,sodium dodecyl benzene sulfonate, and mixtures thereof.

The cationic counterion of the anionic surfactant is typically a sodiumcation but may alternatively be a potassium, lithium, calcium,magnesium, ammonium cation, or an alkyl ammonium anion having up to 6aliphatic carbon atoms, such as anisopropylammonium,monoethanolammonium, diethanolammonium, or triethanolammonium cation.Ammonium and ethanolammonium salts are generally more soluble than thesodium salts. Mixtures of the above cations may be used.

Suitable cationic surfactants are known compounds and include, forexample, mono-cationic surfactants according to structure (XX) below:

wherein:

-   -   R³¹, R³², R³³ and R³⁴, are independently hydrogen or an organic        group, provided that at least one of R³¹, R³², R³³ and R³⁴ is        not hydrogen, and    -   X⁻ is an anion,        as well as mixtures of such compounds

If one to three of the R³¹, R³², R³³ and R³⁴ groups are each hydrogen,then the compound may be referred to as an amine salt. Some examples ofcationic amine salts include polyethoxylated (2) oleyl/stearyl amine,ethoxylated tallow amine, cocoalkylamine, oleylamine, and tallow alkylamine.

For quaternary ammonium compounds (generally referred to as quats) R³¹,R³², R³³ and R³⁴ may be the same or different organic group, but may notbe hydrogen. In one embodiment, R³¹, R³², R³³ and R³⁴ are each C₈-C₂₄branched or linear hydrocarbon groups which may comprise additionalfunctionality such as, for example, fatty acids or derivatives thereof,including esters of fatty acids and fatty acids with alkoxylated groups;alkyl amido groups; aromatic rings; heterocyclic rings; phosphategroups; epoxy groups; and hydroxyl groups. The nitrogen atom may also bepart of a heterocyclic or aromatic ring system, e.g., cetethylmorpholinium ethosulfate or steapyrium chloride.

Examples of quaternary ammonium compounds of the monoalkyl aminederivative type include: cetyl trimethyl ammonium bromide (also known asCETAB or cetrimonium bromide), cetyl trimethyl ammonium chloride (alsoknown as cetrimonium chloride), myristyl trimethyl ammonium bromide(also known as myrtrimonium bromide or Quaternium-13), stearyl dimethylbenzyl ammonium chloride (also known as stearalkonium chloride), oleyldimethyl benzyl ammonium chloride, (also known as olealkonium chloride),lauryl/myristryl trimethyl ammonium methosulfate (also known ascocotrimonium methosulfate), cetyl dimethyl (2)hydroxyethyl ammoniumdihydrogen phosphate (also known as hydroxyethyl cetyldimoniumphosphate), babassuamidopropalkonium chloride, cocotrimonium chloride,distearyldimonium chloride, wheat germ-amidopropalkonium chloride,stearyl octyldimonium methosulfate, isostearaminopropalkonium chloride,dihydroxypropyl PEG-5 linoleaminium chloride, PEG-2 stearmoniumchloride, Quaternium 18, Quaternium 80, Quaternium 82, Quaternium 84,behentrimonium chloride, dicetyl dimonium chloride, behentrimoniummethosulfate, tallow trimonium chloride and behenamidopropyl ethyldimonium ethosulfate.

Quaternary ammonium compounds of the dialkyl amine derivative typeinclude, for example, distearyldimonium chloride, dicetyl dimoniumchloride, stearyl octyldimonium methosulfate, dihydrogenatedpalmoylethyl hydroxyethylmonium methosulfate, dipalmitoylethylhydroxyethylmonium methosulfate, dioleoylethyl hydroxyethylmoniummethosulfate, hydroxypropyl bisstearyldimonium chloride, and mixturesthereof.

Quaternary ammonium compounds of the imidazoline derivative typeinclude, for example, isostearyl benzylimidonium chloride, cocoyl benzylhydroxyethyl imidazolinium chloride, cocoyl hydroxyethylimidazoliniumPG-chloride phosphate, Quaternium 32, and stearyl hydroxyethylimidoniumchloride, and mixtures thereof.

Typical cationic surfactants comprise dialkyl derivatives such asdicetyl dimonium chloride and distearyldimonium chloride; branchedand/or unsaturated cationic surfactants such asisostearylaminopropalkonium chloride or olealkonium chloride; long chaincationic surfactants such as stearalkonium chloride and behentrimoniumchloride; as well as mixtures thereof.

Suitable anionic counterions for the cationic surfactant include, forexample, chloride, bromide, methosulfate, ethosulfate, lactate,saccharinate, acetate and phosphate anions.

Suitable nonionic surfactants are known compounds and include amineoxides, fatty alcohols, alkoxylated alcohols, fatty acids, fatty acidesters, and alkanolamides. Suitable amine oxides comprise, (C₁₀-C₂₄)saturated or unsaturated branched or straight chain alkyl dimethyloxides or alkyl amidopropyl amine oxides, such as for example, lauramineoxide, cocamine oxide, stearamine oxide, stearamidopropylamine oxide,palmitamidopropylamine oxide, decylamine oxide as well as mixturesthereof. Suitable fatty alcohols include, for example, (C₁₀-C₂₄)saturated or unsaturated branched or straight chain alcohols, moretypically (C₁₀-C₂₀) saturated or unsaturated branched or straight chainalcohols, such as for example, decyl alcohol, lauryl alcohol, myristylalcohol, cetyl alcohol, stearyl alcohol, oleyl alcohol, linoleyl alcoholand linolenyl alcohol, and mixtures thereof. Suitable alkoxylatedalcohols include alkoxylated, typically ethoxylated, derivatives of(C₁₀-C₂₄) saturated or unsaturated branched or straight chain alcohols,more typically (C₁₀-C₂₀) saturated or unsaturated branched or straightchain alcohols, which may include, on average, from 1 to 22 alkoxylunits per molecule of alkoxylated alcohol, such as, for example,ethoxylated lauryl alcohol having an average of 5 ethylene oxide unitsper molecule. Mixtures of these alkoxylated alcohols may be used.Suitable fatty acids include (C₁₀-C₂₄) saturated or unsaturatedcarboxylic acids, more typically (C₁₀-C₂₂) saturated or unsaturatedcarboxylic acids, such as, for example, lauric acid, oleic acid, stearicacid, myristic acid, cetearic acid, isostearic acid, linoleic acid,linolenic acid, ricinoleic acid, elaidic acid, arichidonic acid,myristoleic acid, and palmitoleic acid, as well as neutralized versionsthereof. Suitable fatty acid esters include esters of (C₁₀-C₂₄)saturated or unsaturated carboxylic acids, more typically (C₁₀-C₂₂)saturated or unsaturated carboxylic acids, for example, propylene glycolisostearate, propylene glycol oleate, glyceryl isostearate, and glyceryloleate, and mixtures thereof. Suitable alkanolamides include aliphaticacid alkanolamides, such as cocamide MEA (coco monoethanolamide) andcocamide MIPA (coco monoisopropanolamide), as well as alkoxylatedalkanolamides, and mixtures thereof.

Suitable amphoteric surfactants are known compounds and include forexample, derivatives of aliphatic secondary and tertiary amines in whichthe aliphatic radical can be straight chain or branched and wherein oneof the aliphatic substituents contains from about 8 to about 18 carbonatoms and one contains an anionic water-solubilizing group as well asmixtures thereof. Specific examples of suitable amphoteric surfactantsinclude the alkali metal, alkaline earth metal, ammonium or substitutedammonium salts of alkyl amphocarboxy glycinates and alkylamphocarboxypropionates, alkyl amphodipropionates, alkylamphodiacetates, alkyl amphoglycinates, and alkyl amphopropionates, aswell as alkyl iminopropionates, alkyl iminodipropionates, and alkylamphopropylsulfonates, such as for example, cocoamphoacetatecocoamphopropionate, cocoamphodiacetate, lauroamphoacetate,lauroamphodiacetate, lauroamphodipropionate, lauroamphodiacetate,cocoamphopropyl sulfonate caproamphodiacetate, caproamphoacetate,caproamphodipropionate, and stearoamphoacetate.

In one embodiment, the amphoteric surfactant comprises sodiumlauroampoacetate, sodium lauroampopropionate, disodiumlauroampodiacetate, sodium cocoamphoacetate, disodium cocoamphodiacetateor a mixture thereof.

Suitable Zwitterionic surfactants are known compounds. Any Zwitterionicsurfactant that is acceptable for use in the intended end useapplication and is chemically stable at the required formulation pH issuitable as the optional Zwitterionic surfactant component of thecomposition of the present invention, including, for example, thosewhich can be broadly described as derivatives of aliphatic quaternaryammonium, phosphonium, and sulfonium compounds in which the aliphaticradicals can be straight chain or branched and wherein one of thealiphatic substituents contains from about 8 to about 24 carbon atomsand one contains an anionic water-solubilizing group such as carboxyl,sulfonate, sulfate, phosphate or phosphonate. Specific examples ofsuitable Zwitterionic surfactants include alkyl betaines, such ascocodimethyl carboxymethyl betaine, lauryl dimethyl carboxymethylbetaine, lauryl dimethyl alpha-carboxy-ethyl betaine, cetyl dimethylcarboxymethyl betaine, lauryl bis-(2-hydroxy-ethyl)carboxy methylbetaine, stearyl bis-(2-hydroxy-propyl)carboxymethyl betaine, oleyldimethyl gamma-carboxypropyl betaine, and laurylbis-(2-hydroxypropyl)alpha-carboxyethyl betaine, amidopropyl betaines,and alkyl sultaines, such as cocodimethyl sulfopropyl betaine,stearyldimethyl sulfopropyl betaine, lauryl dimethyl sulfoethyl betaine,lauryl bis-(2-hydroxy-ethyl)sulfopropyl betaine andalkylamidopropylhydroxy sultaines.

In one embodiment, the personal care composition further comprises anelectrolyte, typically in an amount of up to about 20 pbw per 100 pbw ofthe personal care composition. Suitable electrolytes are known compoundsand include salts of multivalent anions, such as potassiumpyrophosphate, potassium tripolyphosphate, and sodium or potassiumcitrate, salts of multivalent cations, including alkaline earth metalsalts such as calcium chloride and calcium bromide, as well as zinchalides, barium chloride and calcium nitrate, salts of monovalentcations with monovalent anions, including alkali metal or ammoniumhalides, such as potassium chloride, sodium chloride, potassium iodide,sodium bromide, and ammonium bromide, alkali metal or ammonium nitrates,and polyelectrolytes, such as uncapped polyacrylates, polymaleates, orpolycarboxylates, lignin sulfonates or naphthalene sulfonateformaldehyde copolymers.

In one embodiment, the personal care composition comprises water, ananionic surfactant, a structuring agent for the anionic surfactant, anda pH responsive polymer according to the present invention and exhibitsone or more lamellar surfactant phases. “Lamellar surfactant phases” arephases which comprise one or more surfactant bilayers, typically aplurality of surfactant bilayers separated by liquid medium. Lamellarphases include spherulite phases and the typical form of the liquidcrystal G-phase, as well as mixtures thereof. “G-phases”, which aresometimes referred to in the literature as “L_(α) phases”, are typicallypourable, non-Newtonian, anisotropic products that are cloudy lookingand exhibit a characteristic “smeary” appearance on flowing. Lamellarphases can exist in several different forms, including domains ofparallel sheets, which constitute the bulk of the typical G-phasesdescribed above and spherulites formed from a number of concentricspherical shells, each of which is a bilayer of surfactant. In thisspecification the term “G-phase” will be reserved for compositions,which are at least partly of the former type. The spherulites aretypically between 0.1 and 50 microns in diameter and so differfundamentally from micelles. The surfactant phase morphology of thestructured surfactant composition is observed, for example, using anoptical microscope under cross-polarized light at about 40×magnification.

In one embodiment, the personal care composition of the presentinvention exhibits structured surfactant properties, that is,shear-thinning viscosity and a capacity to suspend water insoluble orpartially water soluble components

As used herein in reference to viscosity, the terminology“shear-thinning” means that such viscosity decreases with an increase inshear rate. Shear-thinning may be characterized as a “non-Newtonian”behavior, in that it differs from that of a classical Newtonian fluid,for example, water, in which viscosity is not dependent on shear rate.

As used herein in reference to a component of an aqueous composition,the terminology “water insoluble or partially water soluble components”means that the component is present in the aqueous composition at aconcentration above the solubility limit of the component so that, inthe case of a water insoluble component, the component remainssubstantially non-dissolved in the aqueous composition and, in the caseof a partially water soluble component, at least a portion of suchcomponent remains undissolved in the aqueous composition.

As used herein, characterization of an aqueous composition as “capableof suspending”, or as being “able of suspend” water insoluble orpartially water insoluble components means that the compositionsubstantially resists flotation of such components in the composition orsinking of such components in such composition so that such componentsappear to be neutrally buoyant in such composition and remain at leastsubstantially suspended in such composition under the anticipatedprocessing, storage, and use conditions for such aqueous composition.

In one embodiment, the personal care composition of the presentinvention comprises, based on 100 pbw of the composition from about 5 toabout 40 parts pbw, more typically from about 10 to about 30 pbw, andstill more typically from about 15 to about 25 pbw, of the anionicsurfactant and from about 0.1 to about 25 pbw, more typically, fromabout 0.5 to about 10 pbw, of a structuring agent.

In one embodiment, the pH of the lamellar phase containing personal carecomposition is from about 5.0 to about 7.0, more typically from about5.5 to about 6.5.

Suitable anionic surfactants include those described above. In oneembodiment of the lamellar phase containing personal care composition,the anionic surfactant comprises one or more branched and/or unsaturatedanionic surfactants. Suitable branched anionic surfactants, include, forexample, sodium trideceth sulfate, sodium tridecyl sulfate, ammoniumtrideceth sulfate, and ammonium tridecyl sulfate.

Suitable structuring agents include cationic surfactants, amphotericsurfactants, fatty alcohols, alkoxylated alcohols, fatty acids, fattyacid esters, alkanolamides, amine oxides, and electrolytes, and mixturesthereof. An effective amount of such structuring agent is one thatpromotes and/or does not interfere with the formation of a lamellarsurfactant phase. Suitable cationic surfactants, amphoteric surfactants,fatty alcohols, alkoxylated alcohols, fatty acids, fatty acid esters,alkanolamides, amine oxides, and electrolytes are described above.

Typically, the greater the amount of surfactant present in relation toits solubility, the smaller the amount electrolyte that may be requiredin order to form a structure capable of supporting solid materialsand/or to cause flocculation of the structured surfactant. In oneembodiment, the composition contains a sufficient amount of anelectrolyte to promote formation lamellar surfactant phases.

In one embodiment, the personal care composition of the presentinvention further comprises, typically in an amount of from greater than0 pbw to about 50 pbw, more typically form about 1 to about 30 pbw, per100 pbw of the personal care composition, one or more “benefit agents”that is, materials that provide a personal care benefit, such asmoisturizing or conditioning, to the user of the personal carecomposition, such as, for example, emollients, moisturizers,conditioners, polymers, vitamins, abrasives, UV absorbers, antimicrobialagents, anti-dandruff agents, fragrances, and/or appearance modifyingadditives, such as, for example, colored particles or reflectiveparticles, which may be in the form of a solid, liquid, or gas and maybe insoluble or are only partly soluble in the personal care compositioncomposition. Mixtures of the benefit agents may be used.

In one embodiment, the personal care composition is a hair stylingcomposition. Suitable hair styling compositions may be in the form of agel, mousse, or spray and may be applied to the hair and/or skin, forexample, by hand or by spraying, as appropriate in view of the form ofthe composition.

In one embodiment, the personal care composition is a hair styling gelthat comprises a hair styling polymer, a pH responsive polymer of thepresent invention, and a carrier, such as water, a (C₂-C₆)alkanol, or amixture thereof.

Suitable hair styling polymers typically comprise multiple cationicsites per molecule and include, for example, polyquaternium-11,polyquaternium-4, polyquaternium-7, polyquaternium-16,polyquaternium-28, polyquaternium-44, polyquaternium-46,polyquaternium-55, polyquaternium-68 and polyquaternium-88. Suitablehair styling polymers also include, but are not limited to copolymers ofpolyvinylpyrrolidone, vinyl acetate, polyvinylcaprolactam, methylethermaleic acid, acrylamides, octylacrylamide, butylaminoethyl, crotonicacid, dimethylaminopropyl methacrylate and dimethylaminoethylmethacrylate, and mixtures thereof.

As used herein, the term “mousse” means a composition that is in theform of a foam when applied. In one embodiment, the personal carecomposition is a hair styling mousse is packaged in a pressurizedcontainer and comprises a hair styling polymer, a pH responsive polymerof the present invention, a carrier, such as water, a (C₂-C₆)alkanol, apropellant suitable for foaming the composition when the composition isdispensed from the container. Suitable propellants are liquefiablegases, such as, for example, propane, butane, isobutane, nitrogen,carbon dioxide, nitrous oxide, 1,2-difluoroethane.

In one embodiment, the personal care composition is a hair spraycomposition suitable for spray application from a container that isequipped with a mechanical sprayer, comprising a hair styling polymer, apH responsive polymer of the present invention, and a carrier, such aswater, a (C₂-C₆)alkanol, or a mixture thereof.

In one embodiment, the personal care composition is an aerosol hairspray composition suitable for spray application from a pressurizedcontainer and comprises, a hair styling polymer, a carrier, typically a(C₁-C₆)alkanol or a (C₇-C₁₀) isoparaffin, a pH responsive polymer of thepresent invention, and a propellant suitable for aerosol delivery of thehair spray composition to the hair. Suitable propellants are thosedescribed above in regard to the hair styling mousse embodiment of thepersonal care composition of the present invention.

The hair styling gel, mousse, and hair spray may in each case,optionally further comprise one or more emollients, conditioning agents,shine enhancers, moisture and heat sensitive moieties, or a mixturethereof. Suitable emollients include, for example, PEG-40 castor oil,glycerol, propylene glycol, butylene glycol. Suitable conditioning andshine agents include, for example, quaternized and/or hydrolyzedproteins of honey, soy, wheat, guar or maize, cetyl alcohol, stearylalcohol, ceteareth-20, isopropyl palmitate, cyclopentasiloxane,cyclomethicone, trimethylsilyamodimethicone, phenyltrimethicone,ethoxylated/propylated dimethicone, dimethiconol, panthenol, tocopherolacetate, tocopherol, cetrimmonium chloride, hair keratin and silk aminoacids and ethoxylated/propoxylated waxes of fruit and vegetable origin.

The personal care composition according to the present invention mayoptionally further comprise one or more adjuvants, such as, for example,preservatives such as benzyl alcohol, methyl paraben, propyl paraben andimidazolidinyl urea; pH adjusting agents such as citric acid, succinicacid, phosphoric acid, sodium hydroxide, sodium carbonate; dyes, andsequestering agents such as disodium ethylenediamine tetra-acetate.

In general, personal care compositions may optionally comprise, based on100 pbw of the personal care composition and independently for each suchadjuvant, from about 0 to about 10 pbw, typically from 0.5 pbw to about5.0 pbw, of such optional adjuvants, depending on the desired propertiesof the personal care composition.

The pH responsive polymer of the present application is useful as acomponent in aqueous fluid compositions used in oilfield applications.

In one embodiment, an aqueous fluid composition of the present inventioncomprises water and a pH responsive polymer of the present invention,typically from about 0.05 to about 40 pbw, more typically 0.1 pbw to 20pbw, even more typically form about 1 to about 10 pbw of the pHresponsive polymer per 100 pbw composition, wherein the pH of thecomposition is greater than or equal to about 6, more typically, fromabout 6 to about 10.

In one embodiment, the aqueous fluid composition further comprises oneor more salts. The salt may be intentionally added as a component of thecomposition or may be present in a geologic formation and becomedissolved in the composition when the composition is contacted with theformation.

In one embodiment, the aqueous fluid composition of the presentinvention is used in a method for handling of particles of debris,typically mineral particles, generated during the excavation, such asduring digging, boring, drilling, blasting, dredging, or tunneling, of ageologic formation in the course of constructing a structure, such asfor example, a road, bridge, building, mine, or tunnel, or drilling anoil and/or gas well. The particles generally have a particle sizeranging from a fine powder to coarse gravel, e.g. dust, sand, andgravel. The debris particles are mixed with the aqueous fluidcomposition to form an aqueous particle dispersion and the aqueousparticle dispersion is transported as needed by, for example, pumpingthe dispersion through a conduit. Such particle dispersions typicallycontain, based on 100 pbw of the liquid component of the dispersion, 90pbw to about 99.9 pbw water, from about 0.1 pbw to about 10 pbw pHresponsive polymer, and from about 5 pbw to about 150 pbw mineralparticles. The particle handling method is useful in known particlehandling applications, such as, for example, to transport and placemineral processing waste in underground caverns, to backfill open pitsor quarries, to place clay or other liners in holding or storage, toextinguish and/or contain coal mine fires by deploying quantities ofsolids below ground to seal the fire from sources of oxygen, and to fillpreviously mined cavities with solids to prevent surface subsidence.

In one embodiment, the aqueous fluid composition of the presentinvention is used as the fracturing fluid in a method for hydraulicfracturing of a geologic formation to stimulate the production offluids, such as oil and/or natural gas, from the formation. Thefracturing fluid is injected through a wellbore and against a surface ofthe formation at a pressure and flow rate at least sufficient toinitiate and/or extend one or more fractures in the formation.Typically, the fracturing fluid further comprises a proppant dispersedin the fracturing fluid. Suitable proppants are inorganic particles,such as sand, bauxite particles, or glass beads and are typically in therange of from about 20 to about 40 mesh. Such fracturing fluidcompositions typically contain, based on 100 pbw of the liquid componentof such composition, from about 90 pbw to about 100 pbw water, fromabout 0.1 pbw to about 10 pbw pH responsive polymer, and from about 10pbw to about 150 pbw proppant. The proppant particles are transportedinto fractures in the geologic formation by the pressurized fracturingfluid stream and keep the fractures from closing back down when thestream of fracturing fluid is discontinued. The proppant-filledfractures provide permeable channels through which the formation fluidscan flow to the wellbore and then be withdrawn. Hydraulic fracturingfluids are subject to high temperatures and shear rates.

Another novel aspect of the present invention are the compounds, i.e.,monomers, corresponding to structures III and V. While the HASE polymersaccording to the present invention as described above have thecompounds, the compounds may also be polymerized or copolymerized withother monomers, including those disclosed above, to form yet differentpolymers and copolymers. The different polymers and copolymers can beobtained by polymerization or copolymerization in the manner describedabove for the HASE polymers.

This (co)polymerization may also be conducted by different methods or indifferent solvents. The scope of methods and solvents is well known tothose skilled in the art.

An example of the prevent invention is set forth below. Unless otherwiseindicated, all parts, percentages, and proportions herein are by weight.

EXAMPLE I Monomer Synthesis

The monomer of Example 1A, according to structure (XXI), which isreferred to as “ODD”:

is made as follows. 2-Octyl-1-dodecanol ethoxylate (25 moles of ethyleneoxide per mole, 214 g=0.15 mol) is charged to a 500 ml round-bottom5-neck glass flask equipped with a PTFE blade agitator, temperaturesensor, dry compressed air purge line and a water cooled condenser. Theliquid ethoxylate is warmed to 69° C., stirred, and MEHQ (0.35 g=0.0027mol) is then added. A purge of dry air at approximately 20 ml min⁻¹ ispassed through the liquid and five minutes later methacrylic anhydride(46.7 g=0.303 mol) is added. The temperature is stabilized and heldbetween 70-73° C. for five hours, then the liquid is cooled to 40° C.Methacrylic acid (35.0 g=0.407 mol) and water (67.0 g=3.72 mol) areadded and the liquid product is discharged.

The monomer of Example 1B according to structure (XXII), which isreferred to as “NOPOL”:

is made as follows Nopol alkoxylate (Nopol compound according tostructure (XVI) above, alkoxylated with 5 moles propylene oxide and 25moles ethylene oxide per mole, 201.5 g=0.129 mol) is charged to a 500 mlround-bottom 5-neck glass flask equipped with a PTFE blade agitator,temperature sensor, dry compressed air purge line and a water cooledcondenser. The liquid ethoxylate is warmed to 66° C., stirred, and MEHQ(0.37 g=0.0030 mol) is added. A purge of dry air at approximately 20 mlmin⁻¹ is passed through the liquid and twelve minutes later methacrylicanhydride (40.3 g=0.262 mol) is added. The temperature is stabilized andheld between 70-74° C. for five and a half hours, then the liquid iscooled to 41° C. Methacrylic acid (38.0 g=0.442 mol) and water (65.0g=3.61 mol) are added and the liquid product is discharged.

EXAMPLE 2 Preparation of HASE Systems

The HASE polymers of Examples 2A and 2B and the HASE polymer ofComparative Example C2 are each made according to the procedure setforth below.

Add heat to kettle charge to about 80° C. while purging with N₂.Maintain N₂ blanket throughout run. At about 80° C., add 25% Initiatorsolution and 2% Monomer emulsion. Hold at that temperature for about 15minutes. Feed remainder of monomer emulsion and initiator solution over3 hours. Hold for 30 minutes, and add the chaser solution. Finally, heatto about 80° C. and hold for 30 minutes, and allow to cool. Theingredients used are shown in TABLE I below.

TABLE I Ingredient Materials weight (g) % BOTM* Kettle Charge DeionizedWater 120.00 Rhodapex AB20 @ 29.0% 0.41 0.12 Ammonium persulfate 0.180.18 Monomer Emulsion Deionized Water 67.83 Rhodapex AB20 @ 29.0% 6.90 2Methyl acrylic acid (MAA) 40.00 40 Ethyl acrylate (EA) 56.00 56Component C 60.1% 6.66 4 Initiator Solution Deionized Water 40.00Ammonium Persulfate 0.25 0.25 Chaser Solution Ammonium persulfate 0.180.18 Deionized water 3.00 Total 341.41 *% BOTM means percentage based ontotal monomer weight.

The following hydrophobic monomers (Component C) are employed:

Component C of the reaction mixture used to make the polymer of Example2A was an ODD monomer according to structure (XXI),

Component C of the reaction mixture used to make the polymer of Example2B was a NOPOL monomer according to structure (XXII), and

Component C of the reaction mixture used to make the polymer ofComparative Example C2 was SIPOMER™ BEM monomer (behenyl methacrylate,Rhodia Inc.)

EXAMPLE 3 Latex Coatings

The HASE polymers of Examples 3A, 3B and C3-1 (each analogous to arespective one of the polymers described in Examples 2A, 2B, and C2above), were each then mixed with a paint latex (VALSPAR 153-16 byValspar Corp.) in the necessary quantities to reach a Stormer viscosityof 95 KU (Krebbs Units). The mixtures were tested for viscosity versusshear rate

The viscosity (in units of Pascal seconds (“Pa s”) at very low shearrate (film formation) are given in TABLE II below.

TABLE II Analogous to polymer of Component C Viscosity EX # Example: ofHASE polymer (Pa s) C3-1 C2 SIPOMER BEM * 469 3B 2B NOPOL (monomer 173according to structure (XXII)) 3A 2A ODD (monomer 96 according tostructure (XXI)) * formed polymer and paint latex mixture not of thepresent invention.

The mixtures of the invention exhibited useful viscosity profiles in thelow (0.1 to 7 s-1), medium (7-1000 s-1) and high (1000-10000 s-1) shearrates compared to the comparative mixture. These shear rate rangescorrespond to those commonly encountered during film formation,formulation appearance/mixing and application (spraying, brushing).Viscosity profiles are shown in FIG. 1.

Nopol based HASE polymers present an excellent consistency of viscositytoward the addition of surfactants. This property is of particularinterest when surface active ingredients are post-added to a thickenedbase paint system. FIGS. 2, 3, and 4 show the viscosity at differentshear rates (0.1; 100; and 7197 s⁻¹) as a function of added surfactant(Rhodapex AB20) for an acrylic latex (Valspar15316) thickened withNopol, BEM (C22 hydrophobe) and Lauryl (C12 hydrophobe) based HASEpolymers (Stormer viscosity between 95-110 Krebbs Units (“KU”).

The Nopol thickened system presents an excellent consistency ofviscosity toward added surfactant at low shear rate (sagging range). Itsviscosity remains quasi-constant while the viscosity of BEM drops fromca. 500 Pas. to ca. 150 Pas. with 4 Wt. % added surfactant. This goodviscosity consistency is still visible at 100 s⁻¹ (texture, appearancerange) while in the high shear rate range (7197 s⁻¹ data, processingrange) the lauryl based HASE thickened systems presents the highersensitivity.

The composition of Example 3C was made by thickening a paint latex (30%solids) to a Stormer viscosity of 95 KU using a HASE polymer analogousto that described in Example 2B above. The composition of ComparativeExample C3-2 was made by thickening an analogous paint latex (30%solids) a Stormer viscosity of 95 KU using a commercially available HASEpolymer. Surfactant (sodium dodecyl sulfate (SDS)) was added to thecompositions of Examples 3C and C3-2 and the Stormer viscosity (inKrebbs Units) was measured. Results are given in TABLE III A and Bbelow.

TABLE III A Viscosity for Example 3C SDS (wt %) Stormer Viscosity (KU)0.00 94.4 0.17 92.2 0.35 89.3 0.53 87.6 0.70 85.9 1.97 79.9

TABLE III B Viscosity for Comparative Example C3-2 SDS (wt %) StormerViscosity (KU) 0.00 95.3 0.18 76.6 0.34 68.1 0.52 63.3 0.69 60.6 1.9753.06

The viscosity of the composition of Example 3C was less sensitive toaddition of the surfactant than was that of Comparative Example C3-2.

EXAMPLES 4 TO 14 AND COMPARATIVE EXAMPLES C4 TO C 14 Personal CareCompositions

Each of Examples 4 to 14 include a polymer according to the presentinvention (analogous to that of Example 2B above) derived from a mixtureof 40 wt % methacrylic acid, 56 wt % ethyl acrylate, and 4 wt % of aNOPOL monomer according to structure (XXII) and having a number averagemolecular weight of about 400,000 daltons).

The personal care compositions of Comparative Examples C4 to C7 weremade by mixing together the relative amounts (as wt %) of the materialsset forth in TABLE III below. The personal care compositions of Examples4 to 7 were made by adding the polymer according to the presentinvention to a respective one of the compositions of ComparativeExamples C4 to C7.

The personal care compositions of Examples 4 to 7 and ComparativeExamples C4 to C7 were evaluated by visual inspection to determine ifthe composition contained suspended air bubbles. The results of theevaluation are given in TABLE IV below.

TABLE IV Ex C4 EX C5 Ex C6 Ex C7 Ammonium laureth sulfate 14.5 14.5 14.514.5 cocomonoethanolamine 2.1 2.1 2.1 2.1 Ammonium xylene sulfonate 0.80.8 0.8 0.8 Hydroxypropyl guar — 0.3 — — (Jaguar HP-60, Rhodia inc.)Xanthan gum — — 0.3 — (Rhodicare T, Rhodia Inc.) Acrylates /(C₁₀-C₃₀)alkyl — — — 0.3 acrylate cross-polymer (Carbopol ETD-2020)Water 82.2 81.9 81.9 81.9 Preservative (Glydant) 0.4 0.4 0.4 0.4Suspends air bubbles? No No Partially No Ex 4 Ex 5 Ex 6 Ex 7 Ex C1 90.1EX C2 90.1 EX c3 90.1 Ex C4 90.1 polymer according to present 9.9 9.99.9 9.9 invention Suspends air bubbles? Yes Yes Yes Yes

The personal care compositions of Comparative Examples C8 and C9 weremade by mixing together the relative amounts (as wt %) of the materialsset forth in TABLE IV below. The personal care compositions of Examples8 and 9 were made by adding the polymer according to the presentinvention to a respective one of the compositions of ComparativeExamples C8 and C9.

The personal care compositions of Examples 8 and 9 and ComparativeExamples C8 and C9 were evaluated by visual inspection to determine ifthe composition separated into layers. The results of the evaluation aregiven below in TABLE V below.

TABLE V Ex C8 Ex C9 Ammonium laureth sulfate 13.2 13.2Cocomonoethanolamine 1.9 1.9 Ammonium xylene sulfonate 0.7 0.7Hydroxypropyl Guar 0.3 (Jaguar HP-60, Rhodia inc.)Acrylates/(C₁₀-C₃₀)alkyl acrylate 0.3 cross-polymer (Carbopol ETD-2020Water 74.4 74.4 Preservative (Glydant) 0.4 0.4 Sunflower Oil 9.1 9.1Stability separated separated Ex 8 Ex 9 EX C5 91 EX C6 91 polymeraccording to present 9 9 invention Stability no no separation separation

A clear conditioning bodywash with suspended oil droplets (Example 10)was made by mixing together the following materials in the relativeamounts (as percent by weight (“wt %”)) given below:

Ingredient Amount (wt %) polymer according to present 2 inventionAmmonium laureth sulfate 8.4 Ammonium xylene sulfonate 0.5Cocomonoethanolamine 2 Mineral oil 1 Hydroxypropyl guar 0.2hydroxypropyltrimonium chloride Triethanolamine, fragrance, q.s.preservative Water q.s.

The composition of Example 10 exhibited a viscosity of 920 cP. Visibleoil droplets in the composition of Example 10 remained stable andsuspended after 1 month at 45° C. An analogous composition (ComparativeExample C10) which lacked the polymer according to the presentinvention, but which included 1 wt % hydroxypropyl guar exhibited aviscosity of 4200 cP, but showed oil separation after 1 month at 45° C.

A clear conditioning bodywash with suspended exfoliating beads (Example11) was made by mixing together the following materials in the relativeamounts (as wt %) given below:

Ingredient Amount (wt %) polymer according to present 2 inventionAmmonium laureth sulfate 8.4 Ammonium xylene sulfonate 0.5Cocomonoethanolamine 1.2 Disodium Laureth Sulfosuccinate 2.5 InduchemUnispheres 1 Hydroxypropyl Guar 0.2 Hydroxypropyltrimonium chlorideTriethanolamine, fragrance, q.s. preservative Water q.s.

The composition of Example 11 exhibited a viscosity of 790 cP. Largedense beads remained stable and suspended in the composition of Example11 after 1 month at 45° C. An analogous composition (Comparative ExampleC11) which lacked the polymer according to the present invention, butincluded 1 wt % hydroxypropyl guar exhibited a viscosity of 3940 cP.Beads sedimented from the composition of Comparative Example C11 after 1month at 45° C.

A clear shampoo with suspended oil droplets (Example 12) was made bymixing together the following materials in the relative amounts (as wt%) given below:

Ingredient Amount (wt %) polymer according to present 2 invention sodiumlaureth sulfate 4.2 Cocomonoethanolamine 0.8 Hydroxypropyl Guar 0.2Hydroxypropyltrimonium chloride Safflower oil 1.0 Triethanolamine,fragrance, q.s. preservative Water q.s.

The composition of Example 12 exhibited a viscosity of 860 cP, Visibleoil droplets remained stable and suspended in the composition of Example12 after 1 month at 45 C. An analogous composition (Comparative ExampleC12) which lacked the polymer according to the present invention, butincluded 1 wt % hydroxypropyl guar exhibited a viscosity of 5820 cP. Oilseparated from the composition of Comparative Example C12 after 1 monthat 45° C.

A clear conditioning hair-spray gel with suspended oil droplets (Example13) was made by mixing together the following materials in the relativeamounts (as wt %) given below:

Ingredient Amount (wt %) polymer according to present 2 invention Sodiumlaureth sulfate 0.6 Hydroxypropyl Guar 0.1 Hydroxypropyltrimoniumchloride Amodimethicone 0.2 Sodium Laureth-13 Carboxylate 0.2 MineralOil 1 Polyvinylpyrolidone 5 Triethanolamine, fragrance, q.s.preservative Water q.s.

The composition of Example 13 exhibited a viscosity of 830 cPs Visibleoil droplets remained stable and suspended in the composition of Example13 after 1 month at 45° C. An analogous composition (Comparative ExampleC13) which lacked the polymer according to the present invention, butincluded 1 wt % hydroxypropyl guar exhibited a viscosity of 3950 cP. Oilseparated from the composition of Comparative Example C13 after 1 monthat 45° C.

A clear conditioning hair gel with suspended oil droplets (Example 14)was made by mixing together the following materials in the relativeamounts (as wt %) set forth below:

Ingredient Amount (wt %) polymer according to present 2 invention sodiumlaureth sulfate 0.3 Hydroxypropyl Guar 0.1 Hydroxypropyltrimoniumchloride PEG/PPG 10/2 dimethicone 0.4 Safflower oil 1Polyvinylpyrolidone 5 Triethanolamine, fragrance, q.s. preservativeWater q.s.

The composition of Example 14 exhibited a viscosity of 790 cP. Visibleoil droplets remained stable and suspended in the composition of Example14 after 1 month at 45 C. An analogous composition (Comparative ExampleC14) which lacked the polymer according to the present invention butincluded 1 wt % hydroxypropyl guar exhibited a viscosity of 3290 cP. Oilseparated from the composition of Comparative Example C14 after 1 monthat 45° C.

EXAMPLE 15 Oilfield

The composition of Example 15 was made to evaluate possible use of apolymer according to the present invention derived from a mixture of 40wt % methacrylic acid, 56 wt % ethyl acrylate, and 4 wt % of a NOPOLmonomer according to structure (XXII) and having a number averagemolecular weight of about 400,000 daltons, as a component in an aqueouscomposition for high temperature, high shear rate oilfield applications.

Deionized water was mixed with sodium bicarbonate to make a 300 ppmsodium bicarbonate hardness water. 88 ml of the DI water/sodiumbicarbonate mixture was placed in a laboratory blender and 12 ml of alatex of the polymer according to the present invention (analogous tothe polymer latex of Example 2B above and containing about 30% solids)was added to the mixture while mixing to make an aqueous polymercomposition that exhibited a low viscosity and a milky white appearance.

The pH of the composition was then adjusted to about 6.8 by addition ofabout 0.6 ml of 50% sodium hydroxide. Upon adjustment of the pH, thecomposition became more viscous and changed in appearance from milkywhite to clear and colorless. The composition was then centrifuged toremove any bubbles.

A sample of about 30 ml of the aqueous polymer composition was placed inthe sample cup of a Brookfield PVS high pressure, high temperatureviscometer and the viscosity of the sample was measured as a function ofshear rate at several temperatures from 75° F. to 325° F., in 25° F.increments. The pressure was maintained at 400 pounds per square inch(“psi”). The sample exhibited good shear thinning behavior up to 300° F.The results are tabulated in the TABLE VI below, as viscosity (“q”), incentiPoise (“cP”), and Shear Rate (“σ”), in reciprocal seconds(“sec⁻¹”), at several different temperatures (“T”), in degreesFahrenheit (“F”).

TABLE VI Viscosity, η, for Composition of Example 15 at Shear Rate, σ,and Different Temperatures η (cP) @ T σ (sec⁻¹) 75° F. 100° F. 125° F.150° F. 175° F. 200° F. 0.04 172256 157243 180158 150132 135909 1082530.07 139788 119172 141296 101070 90510 63147 0.10 101188 80365 8459467675 61494 48743 0.21 50757 42297 44575 37254 32729 25541 0.40 2975124555 24136 19946 18353 14582 0.70 17315 15151 14766 12169 11351 90571.01 12995 11196 10425 9030 8030 6631 2.00 7498 6338 5902 5111 4522 38164.00 4524 3746 3391 2917 2590 2216 7.01 2948 2459 2172 1895 1663 142910.00 2260 1887 1666 1432 1257 1099 20.00 1434 1177 1021 885 774 66540.00 929 776 649 559 481 419 69.99 695 564 470 400 343 295 99.95 497468 386 328 282 241 199.99 429 338 273 229 193 165 399.99 323 253 201166 140 118 η (cP) @ T σ (sec⁻¹) 225° F. 250° F. 275° F. 300° F. 325° F.0.04 82177 51361 30817 1580 0.07 44531 32181 18102 5531 0.10 35139 2375111388 1728 0.21 20325 11713 6546 2499 0.40 10979 8680 4751 1697 0.706782 4954 2886 1683 337 1.01 4831 3822 1877 1038 436 2.00 2858 2186 1244403 235 4.00 1771 1301 737 427 293 7.01 1117 863 585 278 120 10.00 873702 450 212 111 20.00 546 432 297 161 60 40.00 343 273 196 111 62 69.99242 197 145 83 44 99.95 196 161 123 70 40 199.99 137 112 88 55 32 399.9997 81 65 42 27

The present invention has been described with particular reference tothe preferred embodiments. It will be obvious to one of ordinary skillin the art that changes and modifications may be made to the abovedescription without departing from the spirit and scope of theinvention.

What is claimed is:
 1. A method for fracturing a geologic formation,comprising directing a stream of an aqueous composition at a surface ofthe formation at a pressure and flow rate at least sufficient toinitiate, extend, or initiate and extend one or more fractures in theformation, the aqueous composition, comprising: (I) water (II) a pHresponsive polymer comprising, based on the total weight of monomericunits, (a) from about 25 to about 70 percent by weight acid monomericunits, each independently comprising a carboxylic acid-functionalsubstituent group, (b) from about 30 to about 70 percent by weightnonionic monomeric units, each independently comprising a nonionicsubstituent group, and (c) from about 0.05 to about 20 percent by weighthydrophobic monomeric units, each independently comprising a functionalgroup according to structure (I):—R¹³—R¹²—R¹¹  (I) wherein: R¹¹ is bicyclo[d.e.f]heptyl orbicyclo[d.e.f]heptenyl, wherein d is 2, 3, or 4, e is 1 or 2, f is 0 or1, and the sum of d+e+f=5, and which may, optionally, be substituted onone or more of the ring carbon atoms by one or more (C₁-C₆)alkyl groups,R¹² is absent, —OC_(v)H_(2v)—,

 or —O—CH(R¹⁶)—CH(R¹⁷)—O—, wherein v is an integer of from 1 to 6, andR¹⁴, R¹⁵, R¹⁶, and R¹⁷ are each independently H or (C₁-C₆)alkyl, R¹³ abivalent polyoxyalkylene group according to structure (VIII):

wherein: p′ is 2 or 3 and q is 2 or 3, provided that p′ is not equal toq, each r is independently an integer of from 1 to about 50, each s isindependently an integer of from 1 to about 50, and t is 1, and (III) atleast one of: (a) one or more surfactants selected from anionicsurfactant, cationic surfactants, nonionic surfactants, amphotericsurfactants, zwitterionic surfactants, and mixtures thereof, and (b)particles dispersed in the composition.
 2. The method of claim 1,wherein the composition comprises, based on 100 parts by weight of thecomposition, from about 0.05 parts by weight to about 20 parts by weightof the pH responsive polymer.
 3. The method of claim 1, wherein thehydrophobic monomer units comprise monomeric units derived from amonomer according to structure (XI):

wherein R²¹ is H or methyl, p′ is 2 or 3 and q is 2 or 3, provided thatp′ is not equal to q, each r is independently an integer of from 1 toabout 50, each s is independently an integer of from 1 to about 50, andt is
 1. 4. The method of claim 1, wherein the one or more surfactantscomprise at least one surfactant selected from amphoteric surfactants,zwitterionic surfactants, and mixtures thereof.
 5. The method of claim1, wherein the composition comprises the particles dispersed in thecomposition.
 6. The method of claim 5, wherein the particles comprise aproppant.
 7. The method of claim 1, wherein R¹¹ is abicyclo[3.1.1]heptyl or bicyclo[2.2.1]heptenyl group that is bonded toR¹², if present, or to R¹³, if R¹² is not present, via its carbon atomat the 2-position or 3-position and is optionally substituted on itscarbon atom at the 7 position by one or two (C₁-C₆)alkyl radicals. 8.The method of claim 1, wherein the hydrophobic monomeric units arederived from a monomer according to structure (VI):

wherein: R₃ is H or CH₃, R₄ is CH₃, M is an integer from about 10 toabout 40; and N is an integer having a value of 1 to M.
 9. The method ofclaim 1, wherein the hydrophobic monomer units comprise monomeric unitsderived from a monomer according to structure (XXII):


10. The method of claim 1, wherein the carboxylic acid monomer unitscomprise monomeric units derived from a monomer selected from the groupconsisting of methacrylic acid, acrylic acid, and combinations thereof.11. The method of claim 1, wherein the nonionic monomer units comprisemonomeric units derived from a monomer selected from ethyl acrylate,ethyl methacrylate, methyl methacrylate, 2-ethylhexyl acrylate, butylacrylate, butyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxybutylmethacrylate, styrene, vinyltoluene, t-butylstyrene, isopropylstyrene,and p-chlorostyrene, vinyl acetate, vinyl butyrate, vinyl caprolate;acrylonitrile, methacrylonitrile, butadiene, isoprene, vinyl chloride,vinylidene chloride, and combinations thereof.
 12. The method of claim6, wherein the proppant comprises particles selected from sand, bauxiteparticles, or glass beads.
 13. The method of claim 8, wherein M is aninteger from about 25 to about
 40. 14. The method of claim 8, wherein Nis an integer having a value of 5 to M.
 15. The method of claim 8,wherein M is an integer from about 25 to about 40 and N is an integerhaving a value of 5 to M.